Consider the voltaic cell shown below:

Sn(s) / Sn2+ (0.150 mol/L) // Pb2+ (0.550 mol/L) / Pb(s)

a) If the cell operates spontaneously, the Eclula will increase, decrease or remain constant over time? Justify.

b) What will be the Ecell when the Pb2+ concentration drops to 0.500 mol/L? c) What will be the concentration of Sn2+ when the Ecell = 0.020 V?

Data: E0 Pb2+/Pb = -0.13 V E0 Sn2+/Sn = -0.14 V